ARTICLE TOOLS

Abstract

In this article, an overview is given concerning facial amphiphiles in nature, bio-, and supramolecular chemistry. In facial amphiphiles, the hydrophilic and hydrophobic parts are separated by the longitudinal axis of molecule, this in contrast to head-tail amphiphiles in which the hydrophilic and hydrophobic groups each occupy one end of an elongated molecule. This different distribution of hydrophilic and hydrophobic groups with respect to the overall molecular shape leads to a variety of functions which are unique for facial amphiphiles, including emulsification and solubilization of hydrophobic compounds, as antibiotics and pore-forming agents in bilayer membranes, and as membrane curvature sensing and regulating agents. In nature facial amphiphiles occur mainly as low molecular weight compounds such as the bile acids, and as a variety of peptides, alone or as part of larger proteins. Synthetic facial amphiphiles have been synthesized ranging from low molecular weight to polymers and dendrimers for the purpose of novel building blocks for supramolecular architectures and to mimic the natural functions of facial amphiphiles. In this article, we gave an overview of the self-assembly and interfacial behavior of both natural as well as synthetic facial amphiphiles and discuss their most important biological functions and applications.